Senior Full-Stack Developer for English/Yiddish AI Voice & Classifieds Platform

We are looking for an experienced senior full-stack developer or small team to build an automated community classifieds matching platform, initially serving the New York tri-state area and designed to expand to more cities. People must be able to describe what they need or advertise an offer entirely through SMS, WhatsApp, or automated telephone conversations. Both English and Yiddish are required at launch. Categories include apartments, jobs, services, lost-and-found, and other classifieds. CORE DELIVERABLES - Automated inbound and outbound voice conversations, SMS, and WhatsApp, sharing one verified user profile across channels. - English/Yiddish understanding and responses, including cross-language matching. Real Yiddish telephone quality must be demonstrated early, not assumed. - Customer profiles, multiple active searches per customer, advertiser listings, category-specific follow-up questions, and matching that respects stated criteria. - Daily newspaper/website/PDF/image imports with OCR where needed, source tracking, and duplicate detection. Initial sources include Dvar Yom and Git Morgen; an administrator can add sources by city. Each source's access and import method must be validated. - Immediate eligible match notifications and contact exchange between customers and advertisers. Unknown listing prices are allowed; repeated copies of the same ad and phone number should not produce duplicate alerts. - Daily availability checks, automatic pause after five operating hours without confirmation, and reactivation when users confirm. Multiple customer searches must be handled individually within a combined check. - Notification scheduling: text alerts while the platform is open; outbound calls only 9 a.m.–10 p.m.; two retries for unanswered calls. Voice-only users receive calls; text-capable callers receive text alerts. - Shabbat/Jewish-holiday closures that pause communications, response deadlines, paid advertising time, and renewals, resuming after the closure ends. - Secure advertiser payments, saved payment methods through a payment provider, an automated telephone payment option, optional automatic renewal, and failed-payment handling. - Administrator dashboard for sources, users, listings, searches, matching, delivery/import failures, pricing, and free/paid mode. BUSINESS RULES The service launches free for everyone, with an administrator switch to enable advertiser billing later. Customers remain free. Paid advertising initially costs an adjustable $10 per listing for 24 operating hours, excluding Shabbat/holiday closures. Advertisers explicitly choose renewal; turning renewal off leaves the current paid period active. Existing advertisers must approve the price before their first charge. In paid mode, unpaid listings do not release contact details or teaser notices to customers. Customer fees and contact-limit bundles are undecided options and should be estimated separately, not assumed in the core scope. DELIVERY EXPECTATIONS We have a detailed requirements document to share before a firm quote. Please propose a phased build with clear acceptance tests, source-code handover, deployment documentation, monitoring, and ongoing service-cost estimates. Use secure account/payment handling, permission-based communications, and reliable background jobs that prevent duplicate messages and charges. We would like to begin with a small paid feasibility milestone, agreed separately, covering a real Yiddish/English phone conversation and representative newspaper extraction. The goal remains the complete platform; please identify any proposed scope changes explicitly. PLEASE INCLUDE IN YOUR PROPOSAL 1. Relevant deployed voice AI, messaging, marketplace, or automation systems, and your exact role. 2. Your approach to validating Yiddish speech and mixed English/Yiddish conversations. 3. Your proposed architecture and communications/payment providers, including secure phone payments and newspaper imports. 4. Whether you work individually or with a team, and your availability. 5. Proposed milestones, estimated timeline, pricing, recurring service costs, and major risks or dependencies. The 3–6 month duration is a preliminary planning estimate, not a fixed delivery commitment. Budget is open for proposals after scope review. Please do not provide a generic chatbot-only proposal.